The balloons have fallen, the bunting's down, and President Obama has been re-elected.

That means Mitt Romney has been defeated — and with him, many election aspects that we presumed to be true. (You know what they say about presume — it makes a pres out of u and me.)

Maybe it's because we're sailing into a new and uncharted century. Maybe it's because of climate change or polar shift or Mayan calendrical mayhem. But the presidential election of 2012 provided a highly unusual, if not unique, set of circumstances.

In any case, here are truisms that may not seem as true as they once did:

The combination of a down economy and high unemployment dooms incumbents. Historically true in recent memory, but most voters alive today have never experienced this degree of "down" before. In the opinion of many people, including former Secretary of Labor Robert Reich writing in the Huffington Post, you'd have to have lived during the Great Depression to have experienced worse economic conditions than what emerged beginning late in 2008.

The economic situation was so dire four years ago, and it took so many years to create the conditions that made it that dire, that to many voters it seems reasonable to assume it will take years to repair. Still, as ABC News points out, you have to go back to Franklin Roosevelt to find someone who was re-elected with such high unemployment statistics and other dreadful economic circumstances.

Presidential candidates need to campaign in states in order to win them. All politics is local, we are told. But in 2012, Obama laser-focused on the battleground states and pretty much ignored other locales — or at least did not campaign in them. NPR librarian Kee Malesky points out that, according to the Campaign 2012 Political Calendar, Obama only visited 11 states in 2012. He won more than two dozen. Perhaps the old saw should be rephrased: All politics is loco.

Undecideds always vote for the challenger. In predicting a "landslide win" for Romney, The Washington Timesopined in October, "history proves that a majority of undecided voters break for the challenger. Mr. Romney will take most of the undecided voters on Election Day — just as Ronald Reagan did against Jimmy Carter in 1980."

The crack in that myth was manifest in one of the last Wall Street Journal/NBC polls — a post-Superstorm Sandy survey — just before the election. "Undecided voters," The Wall Street Journalreported, "said the last few weeks had made them look more favorably on the president than on Mr. Romney."

Now, once and for all, says Larry Sabato, director of the University of Virginia's Center for Politics, "we can throw out the belief that undecideds at the end break heavily for the challenger."

The taller candidate always wins. Conventional wisdom has it that taller presidential candidates usually beat shorter candidates, says Republican consultant and Ronald Reagan biographer Craig Shirley. But "conventional wisdom is a contradiction in terms, because wisdom comes from thinking in an abstract and nontraditional manner," he notes.

Yes. The taller man always wins, except — as Shirley points out — in 1972, George McGovern was taller than Richard Nixon; in 1976, Gerald Ford was taller than Jimmy Carter; and in 2004 , John Kerry was taller than George Bush. Oh yeah, and in 2012, winner Obama, at 6 feet, 1 inch tall, is an inch shorter than Romney.

It ain't over till it's over. Actually, though the fate of Florida was still undecided at the time of Romney's concession speech, it ... was ... over.

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